Objective-shutter.



0. & H. BRUN S.

OBJECTIVE SHUTTER.

APPLICATION FILED NOV. 9,1911.

1,053,152. Patented Feb. 18, 1913.

2 SHEETS SHEET 1.

0. & H. BRUNS. OBJECTIVE SHUTTER.

APPLICATION FILED NOV. 9, 1911.

1,053,152. Patented Feb. 18,1918

2 SHEETSSHEET 2.

Fig-7 MM,

UNITED STATES PATENT OFFICE.

CHRISTIAN BRUNS AND HEINRICH BRUNS, 0F MUNICH, GERMANY, ASSIGIZOR CHRISTIAN BRUNS & OIE.,'G. M. B. H., OF MUNICH, osamnu'r.

Specification of Letters Patent.

Patent-ed Feb. 18, 1913.

' Application filed November 8, 1911. Serial No. 659,420.

To all whom it may concern:

Be it known that we, CHRISTIAN BRUNS and HEINRICH BRUNs, citizens of the German Empire, residing at Munich, Germany, have invented a new and useful Objective Shutter, of which the following is a specification. i

The invention relates to objective shutters fitted for regulating the duration of exposure with a retarding means," which is connected with the actuating mechanism of the shutter and, according as it is set, more or less retards the running down of the shutter Without interrupting this motion. According to the present invention an auxiliary device of this description is to he disposed in such a manner that it can be brought. into an operative position by being connected either with the actuating mechw nism of the shutter or the main retarding means. A. shutter so titted can then also he used for exposures, which are of longer durationthan the longest obtainable with the main retarding means alone.

Non-interruptive retarding appliances are known in various constructional forms; for objective shutters there are principally employed trains of wheels or escapcments. The effect of tlienmin retarding, means on the running down of the shutter can be regulated by coupling a member of the actuating mechanism of the shutter on n vuriahle section of the path, which this memher travels, with the main retarding means.

In order to simplify die manipulation, it is well to combine with the device, by the actuation of which the shutter is set for the duration of exposure desired in each case. :1 second device in such a manner that. the latter, when the exposure setting device is be ing set for a duration not to be attained with the main retarding means alone,brings the auxiliary retarding device into'operntive ielntionto the actuating mechanism without special manipulation. A spring may 6. y. be so disposed as to tend to couple the auxiliary retarding device with the main retarding means, thus bringing about indirectly the said relation, and a lever may be connected to the exposure setting device, which lever interferes withtlie function of the spring, (or as long as the durntion of exposure set for is attainable by the main retarding means alone.

In the unnexeddrawing: Figure 1 is a front elevation of an o-bieetive shutter constructed according to the invention, the an nular cover-plateheing removed and the shutter being shown unwound. Fig. '2 is similar view, the shutter being wound up. Fig. 3 is a section at. right-angles to the axis through the casing of the above shut ter showing the shutter-blades. Fig t a part front view of the cover-platesin ing the device for regulutingthe durut of exposure set for the shortest exiosuz-c possible. Fig. 5 is a. similar View, tic d vice being set for the shortestelxpoeure tainable with the auxiliary retarding device.

Fig. 6 is a similar view, the device being:

set for the longest. exposur attainable with the auxiliary retarding device: is.- an external view corresponding to Figs. to (i.

Three blades 1 (Fig. which form the shutter proper, respectively have fixed pivots 2 and are provided with pins}; which enter slots 14 of a ring 5, which is jouri aled in three guiding graces 5 concentrically with the axis of the shutter. oh this rin in the 'irection of the arrow marked in Fig. 3opens the shutter, the reversed movement closes it again. An actuuting pin 6 is fixed to the. ring 5 and pro jects through a slot 7 (Figs. 1 and 9) of n plate 8. which bears the actuating mocha; nism. the main retarding means and the auxiliary retarding device.

For actuating the shutter by with: the pint a springwlrimi 9 is made i the. spring of which (not shown) r up by rotating the drum in the. iii of the arrow (shown in Fig. 1) by meana lever 10. A link 1] effects the open and closing of the. shutter; This link, w the shutter is not wound up, is in route by means of a projection 11 with astop 1:3

.and is thereby hindered from emln zmimg under the influence of a spring 13 the aurtuating pin 6 by means of a notch ll. When the shutter is lfcing wound up the link 11 first of all passes to and .thro igh 'the position, in which it stands radiallvto the spring-drum, moving with a surface ll. backward and forward against the actuating pin 6. Immediately previous to the link reaching the position shown in Fig. i2. slides with its surface ll from oil the pin (3, so as under the influence of th s 13 to embrace this pin by means of it Qii A movement .of its edges 9", as also that of a pin 17 fixed to the spring-drum is described below.

A. double lever 18,'which is fulcrumed to a fixed pivot 19, serves for releasing the shutter. One arm of this lever projects through to the outside, while the other rests with a pin 20 thereof against the pivoted catch 14. On the shutter being released by turning the lever 18 inthe direction of the arrow shown in Fig. 2, the spring-drum returns to its position as shown in Fig. 1. During this action the link 11 first of all shifts, through acting on the pin 6, the ring 5 in the direction of the arrow shown in Fig. 3 and so opens the shutter, then passes through the position,'in which it stands radially to the spn'ngdrum, reverses dur ing this action its direction of motion and closes the shutter again. Shortly before the i link'reaches its position as shown in Fig. 1,

it strikes. with its projection 11 the stop 12 and is by this means pushed off, so that it ceases to embrace with its notch 11 the pin 6.

The main retarding means consists of five toothed wheels 21, 21, 21, 21 21 Av springZQ seeks to bring a double lever 23, which'is fulcr unied to a 'fixedpivot 24, into the position as shown in Fig. The double lever engages by means of one of its arms 23, which is formed as a toothed sector, with the toothed wheel '21 and presses with its other arm 23 against an arm 25 of a lever 25 with several arms. This lBVQY'lS fitted with a tooth-shaped arm 25*, for-the purpose of being able to engage with the recess 9 of the spring-drum, and is fulcrumed to a fixed pivot 25. gThe use of a third arm 25 will be more particularly explained below.

An escape wheel 26, which is permanently connected with the toothed wheel '21, and an anchor 27 with a balance 28 fixed rig idly to it form the auxiliary retarding device. The anchor swings about a pivot 2-9. As the means for bringing the auxiliary retarding device into the operative position there are employed a plate 30, which car,- ries the pivot 29 and is fulcrumed to a fixed pivot 31, and a spring 32, which seeks by means of a pin 33 fixed to the plate to displace the latter in such a manner as to cause the anchor to-engage with the escape wheel 26, i. e. the auxiliary retarding device to be applied to the main retarding means. As a means for connecting this auxiliary device with the exposure setting dea. fixed pivot 41.

immediately.

vice, which latter will be described below, a lever 34 with several arms is emploved. which lever is fulcrumed to a fixed pivot 35 and catches by means of the projection 34 behind the pin 33.

The following device serves for setting the shutter for the duration of exposure: Through a slot 36 (Figs. 4 to 6) of a plate 37, which serves as cover-plate to the shutter, a pin 38 fixed to the third arm 23 of the lever 25 projects, and through a second slot 39 a pin 40 fixed to an arm 34* of the lever 34 projects. The cover plate 37 bears A cam-disk 42 (rotatable about this pivot), the outer circumference of which disk is formed by two cam-curves 42 and 42" and the inner circumference of which has a recess 452 concentric to the pivot 41, tuating wheel 43 (itself rotatable about this pivot and shown in Fig. 7), which wheel coupled to the said disk by means of a pin 44. The rim of this small actuating wheel bears a time-scale 45, to-which an index mark 45 on the c0ver-plate corresponds. The outer circumference of the disks-2 allows, according as it is set, the pin 38 to approach'the disk-center more or less, and so allows the tooth 25 to enter more or lessdeeply within the recess The recess 42" is so disposed that the pin 40 is hold fast in a notch 41* of the pivot 41 so long as the path of the pin 38 toward the center of the disk 42 is limited by the curve 4% (Fig 4); the lever 34 then holds with its projection 34 the plate 30 fast by its pin 33 and thereby prevents the spring ing the auxiliary retarding'devi ce. howeverthe cam-disk is set in such a way that the path of the pin 38 is limited by the curve 42* (Figs. 5 and 6), the springv 32 can apply the auxiliary retarding device, as in this position the recess 42 permits the pin 40 to move in the slot 39.

The mode of operationof the shutter is as follows: The setting device having first of all the position shown in-Fig. 4, correspond ing to the shortest duration of exposure, the pin 38 is held by the highest point of the curve 42* in its outermost position, so that the tooth 25 cannot engage at all: ,After 32 from applyreleasing the wound up shutter the springdrum therefore flies back entirely unchecked into its position as shown in Fig; 1, the link 11 opening the shut-terand closing it again the counter-clockwise direction out of the position shown in Fig 4, the auxiliary rctarding device still remains inoperative, as the pin 40'is atil hold fast in the notch 41,

move, ther the disk is rotated. The spring 22 therefore causes, when the shutter is being can be set by means of a small -ac-- When the disk is rotated in When but the curve 42" now permits the .pin 38 to such movement being greater, the farwound up, with the help of the lever-arms i 23" and 25 the tooth 25 to enter the recess 9, and so much deeper, the farther the pin 38 can approach the center of the disk. If the wound up shutder be now released, the link 11. when tlltPl'lllg-dlllll'l flies back, again opens the shutter, and on the further movement of the drum the main retarding means is operated, through the edge 9 strik ing the tooth 25", and the movement of the spring-drum is thus retarded. During its further retarded running down the spring drum gradually turns the lever 25 so far, that the tooth 25* ceases to engage with the edge 9*, and the main retarding means thus becomes inactive. The spring-drum then flies back into the position as shown in Fig. 1, the link 11 again closing the shutter. The disk 42 having been shifted so far as to bring the inner end of the curve 42' opposite the pin 38, this position of the parts corresponds to the longest duration of exposure to be attained with the main retarding means alone. If for attaining a still longer duration of ex osure the disk be shifted fart-her so that t 1e movement of the pin 38 in the slot 36 is no longer limited by the curve 42 but by the curve 42* (Fig. 5), the auxiliary retarding device is at the same time applied to the main retarding means, by the pin 40 being released and the spring 32 cansing the anchor to engage. In order that. when the shutter is being wound up. tooth 25 of the lever 25 may be forced to enter the recess 9, the iever 23 must be able under the influence of the spring 22 to turn in the clockwise direct-ion. To such a turning corresponds an oppositely directed one of the escape wheel. however retarded by the anchor, as long as the latter is in its operative position. In order to let the tooth 25 engage, the anchor is therefore, when the shutter is being wound up. put out of its operative position, shortly before the final position is reached, by the pin 17 on the sprlng-drum acting on the arm The motion of this wheel is.

. chor. After the 34 of the lever 34 and so moving the latter that its projection 34 disengages the anshutter is released and during the flying back of the spring'drum the pin 17, hmvever, 34 and the spring 32 applies the auxiliary retarding device again. The outer end of the curve 42 gives the pin 38 less play in the slot 36 than the inner end of the curve 42; for on actuating the setting device and passing from the use of the main retarding means alone to the additional use of the auxiliary retarding device, the increase of the duration of exposure would undergo a jump, were there not at the same time the curve 42" causing, by means of a diminution in the play of the pin 38, the tooth 25" to enter the recess 9 less deeply, so that also in this case the duration of exposure increases uniformly. On the disk 42 being rotated farther, the play of the pin 38 goes on increasing, and at the same time the duration immediately frees the lever of exposure, which latter reaches its greatest value, when the pin has reached the end of the curve 42 (Fig. 6).

Ye claim:

In an objective shutter a set of blades, an actuating mechanism therefor, a device for setting the shutter for different durations of exposure, a main retarding means controlling the actuating mechanlsm and in turn controlled by the setting device, this means consisting of a train of wheels, the last of which wheels is an escape wheel, an anchor adapted to coact with the escape Wheel and means for causing the engagement and disengagement of the anchor and the escape wheel, this latter means being controlled by the setting device.

CHRISTIAN BRUNS. HEINRICH BRUNS. Vlitnesses lVAL'rER GRESITEN, Ricnann NELS. 

